If your installation uses typical
DB2 defaults for U-lock management and lock size, certain WebSphere
Application Server applications that use container-managed Enterprise
beans (CMP beans) might encounter deadlocks. The likelihood of encountering
deadlocks is entirely dependent on the design and execution pattern
of the applications. The potential for deadlocks increases with the
number and frequency of applications driving concurrent transactions
that update the same areas of the DB2 database. If, given the workload
for your applications, the potential for deadlocks is high, consider
using the following DB2 settings:
RRULOCK(YES)
LOCKSIZE(ROW)
For additional details, see the information
about settings for the internal resource lock manager (IRLM) in your
DB2 Installation Guide.
Your applications might qualify for
the optimistic approach to concurrency control management. To determine
whether your applications can use optimistic concurrency control,
see the topic about concurrency control in the z/OS view of the WebSphere
Application Server Information Center.